Sauté the onion in oil, add the spinach, mangetout and peas, cook for approx. 1 min.
Combine the eggs with the milk and curry paste, season. Pour the egg mixture over the vegetables in the pan. Cover and leave to solidify over a low heat for approx. 20 mins., do not allow to dry out. Slide the frittata onto a plate. Garnish with yoghurt and parsley.